1. Field of the Invention
The present invention relates generally to motor fuel conditioning systems. More particularly, the present invention relates to a system for converting liquid motor fuel into a vaporized mixture of motor fuel and free hydrogen immediately before combustion in an engine.
2. Related Art
Internal combustion piston engines are notoriously inefficient. While great improvements have been made in automobile fuel efficiency over the past 25 years or so, most automobile engines still have efficiencies in the range of 20%. This low level of efficiency leads to several problems. Obviously, it imposes a relatively high expense for fuel to operate the vehicle. Second, it consumes large quantities of a finite natural resourcexe2x80x94crude oil. Finally, inefficient engines create pollution, largely because relatively large quantities of fuel remain unburned, and simply go down the exhaust pipe.
When liquid motor fuel is introduced into an internal combustion engine, whether through carburetion or fuel injection, the fuel is typically introduced as an aerosolxe2x80x94small droplets of liquid dispersed in air. This is true whether the fuel is gasoline, diesel, kerosene, propane, etc. The speed of combustion of the fuel is directly related to the total surface areaxe2x80x94and hence the sizexe2x80x94of the fuel droplets. The smaller the droplets, the faster and more complete the combustion. However, the fuel is generally still a liquid, and the brief time of combustion is insufficient to allow complete burning of the fuel. Thus, to obtain the desired combustion energy, more fuel than is theoretically needed must be introduced into a cylinder for each combustion cycle. The excess simply goes down the exhaust pipe and becomes air pollution.
It has been known for some time that if motor fuel is vaporizedxe2x80x94i.e. completely converted to a gaseous vapor before burningxe2x80x94combustion is more complete. The result is much higher efficiency, and lower emissions. In fact, where gaseous fuels are burned, complete or nearly complete combustion is possible even with very rapid reactions, allowing vast increases in efficiency and reductions in emissions.
However, while this principle has been understood for decades, it has not been applied generally. There area a couple of reasons for this. One relates to the difficulty of handling gaseous fuels. When in a liquid form, motor fuels are relatively safe and simple to handle. Liquids are less volatile, and can be easily pumped, etc. However, vaporized motor fuels are far more volatile and difficult to handle. Another issue is safety. A number of systems for vaporizing motor fuels have been tried, including systems that use engine exhaust or coolant heat to vaporize the fuel. Unfortunately, these various attempts have generally proven ineffective and sometimes dangerous, resulting in accidents and injuries. Consequently, such systems have not been put into use.
With concerns over diminishing oil reserves and increasing air pollution, alternative fuels have also become a focus of increasing consideration and study. As a potential motor fuel, hydrogen presents some excellent possibilities. Hydrogen is a very powerful combustion agent, and is as clean a fuel as could be imagined. The only byproduct of hydrogen combustion is waterxe2x80x94no particulates, no greenhouse gasses, no pollutants of any kind. Unfortunately, the production of elemental hydrogen requires considerable input of energy, with the result that pure hydrogen fuel is very expensive. It is also somewhat difficult to handle, frequently requiring cryogenic equipment and high pressure vessels for storage. Consequently, the use of hydrogen as a motor fuel has not developed very far.
It has been recognized that it would be advantageous to develop a viable motor fuel system that can allow the safe vaporization of motor fuels for use in internal combustion engines in gaseous form.
It would also be desirable to obtain the benefits of hydrogen fuel when using a conventional motor fuel.
The invention provides a system for converting motor fuel, comprising an air intake system, an injector nozzle, a heater, and a catalyst. The injector nozzle injects motor fuel into the air intake system to produce an air-fuel mixture. The heater vaporizes the air-fuel mixture, and the catalyst causes hydrogen to be removed from the motor fuel molecules so as to produce a gaseous mixture of air, motor fuel, and free hydrogen suitable for combustion in an internal combustion engine. The system works with a wide variety of motor fuels, and provides greater fuel efficiency and lower emissions.
In accordance with another aspect of the present invention, the invention provides an internal combustion engine, comprising an engine body, an air intake system, a fuel delivery system, a heating system, and a catalyst. The engine body includes a cylinder with an inlet, and the air intake system is coupled to the cylinder inlet. The fuel delivery system includes an injector nozzle, configured to inject motor fuel into the air intake system, so as to produce an air-fuel mixture which is vaporized by the heating system. The catalyst is disposed between the heating system and the inlet of the cylinder, and is configured to remove free hydrogen from the motor fuel by a catalytic reaction as the vaporized air-fuel mixture passes thereover, such that the fuel that enters the inlet of the cylinder for combustion comprises a gaseous mixture of motor fuel and free hydrogen.
In accordance with a more detailed aspect of the present invention, the heating system comprises a series of porous ceramic disks, which heat the air-fuel mixture as it passes therethrough. In one embodiment the catalyst comprises a mesh screen, made of an alloy of about 60% platinum, 30% iridium, and 10% palladium.
Additional features and advantages of the invention will be apparent from the detailed description which follows, taken in conjunction with the accompanying drawings, which together illustrate, by way of example, features of the invention.